Granite is which pure substance and mixture
The correct answer and explanation is:
Granite is a heterogeneous mixture.
Granite is not a pure substance but a type of rock composed of different minerals. It typically contains minerals like quartz, feldspar, mica, and other trace minerals. These components are not chemically bonded together but are physically mixed, which makes granite a heterogeneous mixture. In a heterogeneous mixture, the individual components can be distinguished from each other by their color, texture, or other properties, and they are not uniformly distributed.
A pure substance, on the other hand, has a uniform composition throughout and consists of only one type of atom or molecule. Examples of pure substances include elements like gold or compounds like water. Granite does not meet these criteria because it has varying mineral contents throughout its structure, and the mineral grains are not uniform in size, color, or chemical makeup.
In granite, the quartz is usually transparent or white, feldspar can appear pink or white, and mica gives the rock a shiny appearance due to its black or silvery sheets. The mineralogical diversity within granite is what gives it its characteristic appearance. If you were to examine a piece of granite under a microscope, you would see the different mineral grains clearly.
Granite forms from the slow crystallization of magma beneath the Earth’s surface. This slow cooling allows the different minerals to form distinct crystals, further contributing to the heterogeneous nature of the rock. Despite being a mixture, granite is often considered a solid rock used in construction and countertops due to its durability, aesthetic appeal, and the ease with which it can be cut and polished. However, chemically, granite does not fall into the category of a pure substance.